Plow or the like and method of making same



- Patented Jan. 25, 1949 v e T MAKING; SAME .Reuel n. Figard, Detroitimicliifassignor 'to flarry yerguson, Inc., Dearboi'ii, -Michifal dr ioration iifmelaware Drawing; Applicati dfillahuary 20,1945,

' 1P3 Serial No. 573,815

1 2 According 't'othe present inventiom'l 'overr difiiculty byproviding on the earth hile iii use and-to tli'od of ma]; 'g' "them Working'surface of a plow'or' the like, which has armmote particularly try-earth woiki previously been fabricated in any suitabl manments 'l i'aving a new-and 'impibved 'artliengag- 5* her tobring the surface to its proper'-for'rn jan.d

ing suffiice produced theredn by a noifelihethod. shape, a smooth dull finish'which is free of In such implements as plows one serious difiigrinding wheel marks and is comprised of exculty in the production thereof is in the-.developiremely minute projections which cover the surment of a finished ground engaging surface that face and produce its dull appearance. Such a will scour. A plow, for example, is given as close surface is capable of being finished by the abradto a proper shape as can be designed to meet a ing, polishing action of the earth moving across known soil condition and the curved turning surit, the dull surface being, in effect, burnished face is then ground and highly polished by a relto a smooth, good scouring condition. atively costly process to obtain a smooth surface. The dull smooth finish may be produced on Even so, the plows do not always scour satisfacthe surface quickly and effectively by forcing torily. It is believed that this failure of the tools small particles of an abrasive agent against the is due in part at least to the small lines and other surface. A wet blast method of surface treatirregularities produced in. the surface by the ment has been found to be quite effective in grinding wheel. producing a surface which is smooth, in which An object of the invention is to provide a plow 2 the minute projections from the surface are quite or like earth working implement which has a uniform and in which siu'face scratches or wheel smooth earth working surface of proper form marks are substantially absent. Such a method and curvature covered with extremely small proinvolves the discharge of a high velocity Stream jections capable when the tool is first drawn of an oil or fluid borne abradant. e q y through the earth of being, in effect, burnished of abradant used and its fineness determines the thereby to smoothness along lines extending in nature of the finish on the surface. Preferably the direction of earth movement past such sura powdered abradant, such as that known comface during use. mercially as Novaclite, is employed in an oil Another object is to provide a novel process carrier which inhibits oxidation of the finished of producing plows or the like which involves the 3 surface. tep n the fi ng of the earth Working sur- The final step of finishing the surface of the face o providing 011 Said r ace a dull, smooth implement to a condition in which it will scour finish comprised of minute ion and effectively, involves the treatment of the surface fi y polishing t e Surface y the relative by causing an abrading or polishing medium to movement 0f the Surface and an abrading move across the surface along lines which extend dlum along the lines of movement the earth in the direction in which the earth will move past the surface in normal operation ofthe impast the surface during n0rma1use This may be plementdone during the manufacture of the implement,

The i may be employed F but may be most efficiently and effectively perfgeously m F with earth working 40 formed by the action of the earth on the surface 1.111191611181115 having an earth workmg surfafize and during the initial stages of the actual operation It IS partlcularly Wen adapted for Such lmple' of the implement in the ground. The abrading ments as plows, listers, middlebusters ,andthe. like in which the earth working surfaces must scour. This term, of course, refers tothe 'movement of the earth across a surface freely, cleanly and without tending to adhere thereto.

Heretofore the final finish on the earth working surface of an implement of this character has been produced by one or more grinding oper- 5 among such Operations inevitably leave, wheel line of earth flow and hence cannot interrupt the or abrasive marks in the finished surface extendclean free movement of the earth across the ing somewhat hap-hazardly in allgdirections. face- Such marks would of course interfere with the An earth Working implement finished in this desired free earth movement tthi surface, 5 manner will have high scouring characteristics burnishing effect of the earth moving relatively to the particle covered surface will polish the surface. Since the direction or relative movement of the earth and the surface is the result of the use of the implement in normal operation, any surface scratches, marks or lines that may be formed in the implement surface will parallel the 3 after the implement has been used a relatively short time.

What I claim is: 1. The method of manufacturing a plow which includes the steps of forming the earth-engaging surface of a curvature suitable for turning a particular kind of earth, treating the surface'by a blast of abrasive particles to eliminate scratches or wheel marks and to produce a uniform surface of dull appearance comprised of extremely minute projections, and then polishing said surface by causing a polishing agent to move across the-- I? -1 I .4 tective material to form a residual protective film and thus prevent oxidation of the bare metal surface exposed by the action of the abrasive particles, and then polishing the unoxidized surface by causing a polishing medium to move across the surface along lineswhich extend in the direction in which the earth will move past the surface during normal use, thereby producing a surface in which any lines left by the polishing process are parallel to the line of earth flow and hence cannot interrupt the clean free movement of earth across the surface.

- REUEL-H. FIGARD.

. file 'of this patent:

rying abrasive particles to eliminate scratches and wheel marks and to produce a uniform dull surface comprised of extremely minute projections, said liquid consisting of oil or the like pro- UNITED STATES PATENTS Number 

